January 2011 unusually cold in Japan

Cold weather settled over Japan and the Korean Peninsula in January 2011, and for the first time since 1986, Japan experienced below-normal January temperatures.

The map above shows differences from average temperature across Japan and eastern China in January 2011. Shades of red indicate areas that were up to 9 degrees Fahrenheit warmer than the long-term (1981-2010) average, while shades of dark blue indicate places that were up to 9 degrees F cooler than average. Light colors indicate areas where temperatures were closer to average.

The unusually wintry weather was due to an enhanced East Asia winter monsoon, during which cold, high-pressure air from Asia flows offshore and collides with warmer, wetter air over the Pacific.

Map based on daily composites of temperature data from the NCEP/NCAR Reanalysis project, provided by NOAA Earth System Research Laboratory.